2023 QA/QC

Published

February 28, 2024

Introduction

Prior to publishing analysis and interpretation of water quality data, we will ensure that all data that meets QA/QC standards outlined in the current project Quality Assurance Project Plan (QAPP) and is accessible in the appropriate public repository.

Water quality data from this project is ultimately destined for public archival in the Environmental Protection Agency’s Water Quality Exchange (EPA WQX).

The QAPP for this project describes data management details and responsible parties for each step of the data pipeline from observation to repository. The 2023 data preparation and review process is published here.

Year 2023 Water Quality Data

In this chapter we will collate 2023 laboratory data from several sources into a single spreadsheet document with a consistent format. The desired end format is a spreadsheet template provided by the EPA Water Quality Exchange. These template files are available to download from the EPA at https://www.epa.gov/waterdata/water-quality-exchange-web-template-files.

Once the data is collated, it will be evaluated according to a Quality Assurance Checklist (template example provided by the Alaska Department of Environmental Conservation Soldotna office). Field observations that do not meet the quality assurance standards described in the evaluation checklist will be flagged as “Rejected” before being uploaded to the EPA WQX.

Data that has been uploaded to the EPA WQX is evaluated biannually by the Alaska Department of Environmental Conservation (ADEC) in their Integrated Water Quality Monitoring and Assessment Report1. The integrated report evaluates available water quality data from the previous five years against Alaska water quality standards and regulations (adec2020?).

2023 Water Quality Data Formatting

The code scripts in this document assemble water quality data from the two analytical laboratories that partnered with Kenai Watershed Forum for this project in 2023:

  • SGS Laboratories (Anchorage, AK)

  • Soldotna Wastewater Treatment Plant (Soldotna, AK)



2023 Metals/Nutrients Lab Results (SGS Labs)


–> use EPA metals guidance in QA/QC rather than at this stage!

check all these again, make decision if static, concatenated, or formulaic

general strategy: get all columns of sgs data to conform to final CDX format before joining. (e.g. do all sgs first, then swwtp)

there are pieces and parts existing in the 2021 script, but to stay organized it would make sense to proceed L –> R for each column


2023 Fecal Coliform Lab Results (Soldotna Wastewater Treatment Plant Lab)

Chain of custody documents available upon request.

value for "which" not specified, defaulting to c("rows", "cols")
Joining with `by = join_by(sample_location_rm)`


2023 Total Suspended Solids Lab Results (Soldotna Wastewater Treatment Plant (SWWTP))

Chain of custody documents available upon request

New names:
New names:
• `` -> `...8`
Warning: There was 1 warning in `mutate()`.
ℹ In argument: `time_sampled = format(...)`.
Caused by warning in `as.POSIXct()`:
! NAs introduced by coercion
value for "which" not specified, defaulting to c("rows", "cols")
Joining with `by = join_by(sample_location)`
Warning: Unknown columns: `project_id`, `activity_media_name`,
`activity_media_subdivision_name`, `activity_start_time_zone`,
`activity_latitude`, `activity_longitude`, `activity_depth_height_measure`,
`activity_depth_height_unit`, `activity_comment`,
`activity_horizontal_collection_method`, `activity_horizontal_reference_datum`,
`result_weight_basis`, `result_value_type`, `sample_collection_equipment_name`,
`result_status_id`, `laboratory_comment_text`, `thermal_preservative_used`
Warning: Unknown columns: `project_id`, `activity_media_name`,
`activity_media_subdivision_name`, `activity_start_date`,
`activity_start_time_zone`, `activity_latitude`, `activity_longitude`,
`activity_depth_height_measure`, `activity_depth_height_unit`,
`activity_comment`, `activity_horizontal_collection_method`,
`activity_horizontal_reference_datum`, `result_weight_basis`,
`method_speciation`, `result_value_type`, `sample_collection_equipment_name`,
`result_status_id`, `laboratory_comment_text`, `thermal_preservative_used`
Warning: Unknown columns: `project_id`, `activity_media_name`,
`activity_media_subdivision_name`, `activity_start_time_zone`,
`activity_latitude`, `activity_longitude`, `activity_depth_height_measure`,
`activity_depth_height_unit`, `activity_comment`,
`activity_horizontal_collection_method`, `activity_horizontal_reference_datum`,
`result_weight_basis`, `method_speciation`, `result_value_type`,
`sample_collection_equipment_name`, `result_status_id`,
`laboratory_comment_text`, `thermal_preservative_used`
Rows: 22 Columns: 3
── Column specification ────────────────────────────────────────────────────────
Delimiter: ","
dbl (3): monitoring_location_id, activity_latitude, activity_longitude

ℹ Use `spec()` to retrieve the full column specification for this data.
ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.
Joining with `by = join_by(monitoring_location_id)`

2023 Data QA/QC Evaluation

Prior to upload to the EPA WQX, all water quality data must be checked against a series of standard questions in order to evaluate how quality assurance / quality check (QA/QC) requirements are met. The draft Data Evaluation Checklist Template (available for download below) outlines these questions:

Download results pre-QA/QC; including lab QA QC info

Pre-database

Overall project success

1.) Were the appropriate analytical methods used for all parameters?

Yes. Analytical methods from the approved 2020 QAPP were employed.


2.) Were there any deviations from the sampling plan?

Yes. One site in spring 2023 could not be accessed for sampling due to low water conditions (Kenai River main stem, RM 10.1).


3.) Were field duplicates, blanks, and/or other QC samples collected as planned?


  1. https://dec.alaska.gov/water/water-quality/integrated-report/↩︎